Mountable retention clips that retain tubular members have many well known applications and are enormously successful in the market place. In the automobile industry for example these clips are used to retain and mount a variety of tubular members including brake lines, fuel lines and electrical cable bundles to a mounting member such as a chassis or unibody structure. The clips are generally formed of a plastic material to reduce weight and cost. In some applications, the clips are first mounted on the mounting member and then the tubular members are retained in the mounted clips. In other applications, tubular members are first retained in several clips to form an assembly, which is later mounted on a mounting member such as automobile frame. U.S. Pat. No. 4,881,705 to Kraus for example discusses a plastic holding element having a hinged cover part that is closable over tubular members retained by a separate inlay part housed in a base part. The cover part is closed over the base part and secured in the closed position by a single resilient catch. The separate inlay however requires additional fabrication and subsequent assembly, which increases costs. The single catch is also susceptible to failure during handling of holding elements assembled with tubular members before mounting and when subject to vibrational stress after mounting. The single catch of course may be made more reliable by increasing its contact surface areas to increase the holding force on the cover pan. This solution however the requires additional material to fabricate the catch, which disadvantageously increases the overall size and weight of the clip. Moreover, an enlarged catch requires exertion of additional force or pressure to fasten the catch, which when performed manually is a known cause of physical fatigue and a suspected cause of carpel tunnel syndrome and other debilitating maladies.
Others have endeavored to improve the reliability of the clip by increasing the holding force on the cover part with additional separate components. U.S. Pat. No. 5,301,831 to Dyer for example discusses a clip having a cover with resilient edge portions that snap fit over edges of a flange on a U-shaped housing. A fastening member is disposed through an aperture through both the cover and the flange to mount the housing to a mounting surface and secure the cover to the flange. This type of clip however can not be mounted on the mounting surface until after inserting the tubular members into the housing and closing the cover over the flange. Also, the housing must be removed from the mounting surface before opening the cover from the flange to gain access to the tubular members. In addition, the resilient cover is susceptible to inadvertent opening during handling and installation since an opening force on the cover has a tendency to unsnap both resilient edges of the cover from the flange. U.S. Pat. No. 5,423,831 to Nates discusses a disposable clamp with improved latching performance, but the amount of pressure required to manually latch the clamp is a source of physical fatigue. Further, the clamp is specifically intended for stemming the flow of blood through a mammalian umbilical cord after birth and for safety purposes has the disadvantage that the latch must be destroyed to open the clamp, which is preferably removed only upon natural separation of the umbilical cord.